Abstract

Somatic embryogenesis in conifers is a breakthrough for micropropagation. From a single immature or mature embryo or from cotyledons, an embryogenic tissue can be obtained from which an unlimited number of propagules can be produced. It is a tissue culture process that mimics zygotic embryogenesis, resulting in the production of somatic embryos that mature, germinate, and form plantlets. This tissue culture method is now widely used for clonal plantlet production and for other types of studies, such as genetic transformation. Because of numerous requests for information on the protocols developed in the authors' laboratories, this guide has been assembled to assist those who want to use somatic embryogenesis in spruce and larch. It covers all the important steps in the production of embryogenic tissue and in plantlet regeneration. In each section, the literature published on the topic under consideration is reviewed so that the reader can refer to original published work. In addition, the guide covers special applications such as protoplast isolation from embryogenic cell lines and cryopreservation of tissues.